What causes bad breath even after brushing? Here’s 10 reasons why!

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Has it ever occurred to you that even after you brushed your teeth, your breath smells awful? But why and what causes bad breath even after brushing? 

Bad breath, scientifically referred to as halitosis, is the foul and unpleasant smell of the breath. This can happen due to a wide variety of reasons. In this article, we will dive deep into all these reasons and what to do to get rid of this inconvenient condition.

So what causes bad breath even after brushing? Let’s explain, shall we begin?

I brushed my teeth but I still have bad breath: 10 possible reasons explained

Many people complain that despite brushing, they still have foul-smelling breath. Halitosis doesn’t necessarily mean you don’t brush your teeth. Several factors can contribute to an unpleasant breath despite brushing. Here we will talk about all the possible reasons from the most to the least common ones. So what causes bad breath even after brusing? Here are 10 possible reasons for halitosis:

  1. Poor dental health
  2. You have gum disease and you are not aware of it
  3. You forget to brush your tongue
  4. Dental appliances that do not fit properly can be the cause
  5. It can be because of what you eat or drink
  6. Dry mouth
  7. Post-nasal drip could be the reason
  8. Maybe you have other underlying health conditions
  9. Medications you’re using
  10. Tonsil stones are to blame

Now, without further ado let’s dive deep into each one of them. 

1. Poor dental health

You might brush your teeth, but it’s not efficient enough. Sometimes you might not be able to reach all the hidden spaces, especially if you have crooked teeth. When you don’t brush your gum lines or all the spaces around your teeth the food remnants, dead cells, and bacteria stay in the mouth. As time goes on, more particles accumulate, and they start to create a terrible smell. For better oral hygiene and fresh breath, in addition to regular brushing, flossing and rinsing with mouthwash are essential. In cases of difficulty reaching some parts of the oral cavity such as crooked teeth, water floss is a big help for washing away the bacteria and debris.

This is why you should regularly visit your dentist and do dental cleanings. You can also ask your dentist to teach you how to brush your teeth effectively.

2. You have gum disease and you are not aware of it

You wash your mouth daily and still feel a disgusting smell coming out of your mouth. Are you wondering what causes bad breath even after brushing? You might have gum disease. Plaque or tartar build-ups are concentrations of bacteria that cause a stinky odor. They engage the gum line, causing swollen and bleeding gums, and infection. If left untreated, this situation develops into gum disease, causing an unpleasant smell.

On the other hand, you might have cavities or tooth decay and not be aware of that. Bacteria can hide inside those cavities as well as gum pockets, worsen the situation and produce stinky bad breath.

Surgical wounds following an oral procedure can cause this bad smell. Examples are a wound after a tooth extraction or oral surgery. Following a tooth extraction, food can get stuck in the empty tooth socket. It can be removed with a water flosser or toothpick to avoid the consequences.

This is preventable by practicing a regular oral hygiene routine. In the case of plaque build-up or tartar, cleaning sessions are required. It is essential to treat the underlying gum disease to preserve the gum tissue and get rid of that terrible smell.

Make sure to be in touch with your dentist if you feel halitosis after a dental procedure.

3. You forget to brush your tongue

Under the microscope, the surface of the tongue is covered with very tiny bumps called papillae. This is an ideal place for food particles and bacteria to accumulate. If the person doesn’t brush the tongue surface regularly, these accumulations remain in the mouth and produce a foul odor. People who smoke or have dry mouths may also experience bad breath from their tongues.

Tongue cleaners, tongue scrapers, or tongue brushes are ideal devices to prevent this from happening. Toothbrushes that have a tongue cleaner on one side are beneficial and economical.

4. Dental appliances that do not fit properly can be the cause

Dental appliances in the mouth like bridges, braces, or dentures are used to correct dental problems and bite abnormalities. If they do not fit properly it can be a possible reason for the disgusting breath. This is because food particles can go underneath the device that a toothbrush can not reach. They remain there and create a foul smell. On the hand when the dental appliances are not fitting well, can cause oral complications such as gum disease or infections, which are other causes of bad breath.

5. It can be because of what you eat or drink

Persistent consumption of foods that are high in sulfur, foods that cause mouth dryness, or allergy-causing foods leads to a foul smell. These foods should be consumed in lesser portions and in case of allergy, they should be avoided.

Coffee lovers should know brushing and gargling with mouthwash is recommended after drinking it. Coffee consists of acidic and sulfuric compounds, and in addition to that, reduces saliva production. It is better to have your coffee dark and with less sugar, as sugar helps bacterial growth. The same can be said about tea. Drinking water after coffee or tea will help with the smell.


If you are a drinker and wonder what causes bad breath even after brushing, you might want to reconsider your life choices. Firstly, alcohol leads to dehydration which is a key factor in halitosis. Secondly, drinking decreases the population of useful or good bacteria in the mouth. If the balance is ruined, then the bad bacteria in your mouth start to cause a foul smell.

Alcohol increases the risk of gastric reflux, which is an important cause of unpleasant breath. Above all, alcohol turns into a type of acid in the body, thus bad breath.

Reducing alcohol consumption might be beneficial not only for your breath but also for your overall health.

If you’re smoking that could be the problem

Smoking can lead to bad breath in different ways. Smoking cause dehydration and a severely dried mouth. Tobacco particles cause gum irritation and can develop gum diseases. These components also create a stinky breath by getting stuck between the tongue papillae. Chewing tobacco and smoking pipes almost affect the same way.

For fresh breath and a healthy body, you should quit smoking, as well as drink plenty of water. Do not forget to maintain your oral hygiene by practicing a regular routine.

6. Dry mouth

Saliva is essential for washing away the accumulated bacterial colonies and neutralizing the acid produced by these bacteria in the tartar or plaques build-ups. Every day many cells in the oral cavity die and are replaced by new ones. Saliva washes these dead cells from the mouth, preventing them from staying for a long time and causing bad breath. People who sleep with their mouths open, tend to suffer more from a dry mouth when they wake up to a terrible breath.

  • One reason for mouth dryness is dehydration: make sure you drink plenty of water every day, to avoid having an unpleasant breath as well as having a healthy body.
  • Another reason is smoking.
  • Medication is also another reason: consult your doctor about this problem. Ask for an alternative option with fewer side effects. If not possible, ask for ways to reduce this unwanted unpleasant odor.

7. Post-nasal drip could be the reason

Another reason for bad breath from throat is post-nasal drip. Abnormal mucus gathering at the back of the throat or excessive mucus discharge dripping from the nose or sinuses to the throat is called post-nasal drip. This is a common cause of chronic coughing.

Mucus traps bacteria as an immune response. When these bacteria are accumulated in the back of the throat, they produce a foul smell. Post-nasal drip can happen as a result of a cold, GERD, sinus infection, bacterial infection, allergies, or pregnancy. A disorder called cystic fibrosis which is associated with the production of a large amount of thick mucus is another reason behind excessive post-nasal drip.

By treating the underlying reason, the post-nasal drip and the bad breath associated with it will go away. Drinking plenty of water is always a good option to recover faster ad better.

8. Maybe you have other underlying health conditions

Sometimes bad breath that doesn’t go away with brushing and flossing can indicate a serious medical condition that requires treatment and medical intervention. But what are these health conditions?

  • You may have GERD (reflux)
  • Respiratory diseases
  • Constant vomiting
  • Sinus infection
  • Ketoacidosis
  • Peptic ulcer
  • Liver failure
  • Kidney disorders
  • Intestinal obstruction
  • Cancers

You may have GERD (reflux)

Gastroesophageal reflux disease is a condition in which the acidic stomach contents and stomach acid get back up to the esophagus. To explain it in simple words, consider the entrance between the esophagus and the stomach as a muscle ring. 

When LES loses the ability to fully close when the food passes from the esophagus to the stomach, the stomach’s acidic contents are moved back up to the throat. Besides the common symptoms which are heartburn and a sour or bitter taste, an unpleasant odor also occurs due to the undigested food combined with stomach acid.

Mostly, the condition can be cured by medications and changes in lifestyle. If these solutions fail to solve the problem, the next option is surgery.

Respiratory diseases

Respiratory infections such as bronchitis, pneumonia, viral colds, or flu cause the patient’s breath to smell bad. Any bacterial accumulation in one part of the body can cause a disgusting smell due to their activities and the products they produce. This is especially very common in upper respiratory infections. Lower respiratory infections such as lung abscesses, bronchiectasis, and interstitial lung disease have their own fair share of causing a foul-smelling breath.

People with asthma also might experience halitosis due to mouth breathing. Breathing through the mouth causes mouth dryness which is a major underlying reason for this bad smell.

In cystic fibrosis due to the production of thick mucus, especially in the respiratory system, lung infection is very common. This is another potential reason for halitosis.

New studies have revealed halitosis is a confirmed complication of covid-19 in an outstanding number of patients.

Medical intervention is necessary for lung diseases. Antibiotics and inhalers are the frontline treatments. However, excessive use of an inhaler can cause the mouth to go dry, exacerbating the condition. That’s why you should always keep in touch with your doctor.

Constant vomiting

Chronic vomiting is another factor for dragon breath. No fires and flying here. This is not the house of the dragon we are talking about, but the unpleasant breath even after brushing. Besides causing dehydration, vomiting brings up acidic or fermented food from the stomach or even from the intestines, leading to a stinky breath. Treatment depends on the cause of the vomiting whether it’s food poisoning, intestinal obstruction, liver failure, ketoacidosis, cancer, or any other reason.

The doctors focus on anti-vomiting medications and hydrating the patients, and curing the main problem.

9. Medications

You might be shocked if we tell you medications are another reason for the foul odor. But how?

Different medications can reduce saliva production and cause a dry mouth. The most common drugs in this category are antihistamines, chemotherapeutic agents, antidepressants, acid-reducers, and dietary supplements. Another reason is medications can break into smaller chemical particles inside the body. These particles can lead to an embarrassing odor.

Usually, the smell fades away once the treatment is over. If the bad breath remains, consult with your doctor about your concerns. Undoubtedly they know how to handle the situation.

10. Tonsil stones are to blame

Tonsil stones are hardened debris formations in your tonsils that are filled with odor-causing bacteria. These formations consist of food, dead cells, or mucus that hardened or calcified. The most common symptoms of tonsil stones are bad breath and sore throat.

A common reason for bad breath in children is tonsilitis or the inflammation of the tonsils due to an infection. This is easily curable by prescribing medications and proper care.

Usually, they are easily removable by gargling with salt water and using a cotton swab. If they are very large and recurrent, your doctor might suggest surgery to remove them. This is not the expertise of dentistry, you may consult your ENT doctor.


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